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Constellation program

In December 2007 NASA named the lunar lander
Altair, after the brightest star in the constellation Aquila. Aquila is the Latin word for Eagle, which was also the name of the first manned spacecraft to land on the Moon, Apollo 11’s lunar module.
Altair would have been a two-stage spacecraft (a descent stage and an ascent stage) and would have landed four astronauts on the Moon. Its launch mass...